Vehicle control device, vehicle control method, and storage medium

ABSTRACT

A vehicle control device in an embodiment includes a recognition unit that recognizes a surrounding situation of a vehicle and a driving control unit that controls one or both of steering and acceleration or deceleration of the vehicle on the basis of the surrounding situation recognized by the recognition unit, and in a case where the vehicle merges into a second lane from a first lane in which the vehicle travels, and a section of the second lane before merging recognized by the recognition unit is downhill, the driving control unit makes a speed or acceleration of the vehicle higher than in a case where the section before merging is not downhill.

CROSS-REFERENCE TO RELATED APPLICATION

Priority is claimed on Japanese Patent Application No. 2018-216433,filed Nov. 19, 2018, the content of which is incorporated herein byreference.

BACKGROUND Field of the Invention

The present invention relates to a vehicle control device, a vehiclecontrol method, and a storage medium.

Description of Related Art

In recent years, there has been progress in research for recognition ofa surrounding road situation and autonomous control of a vehicle on thebasis of a recognition result. As a method of recognizing a surroundingroad situation, a technique for capturing an image of a road surfacethrough an imaging unit mounted in a vehicle, recognizing a change inthe height of a road surface on the basis of the captured image, anddetermining the type of road on which a vehicle is present with theaddition to a recognition result is known (see, for example, JapaneseUnexamined Patent Application, First Publication No. 2008-32557).

SUMMARY

However, in a specific traveling situation such as merging, appropriatedriving control depending on a road situation may not be able to beexecuted.

The present invention was contrived in view of such circumstances, andone object thereof is to provide a vehicle control device, a vehiclecontrol method, and a storage medium which make it possible to executemore appropriate driving control on the basis of a road situation duringmerging.

A vehicle control device, a vehicle control method, and a storage mediumaccording to this invention have the following configurations adoptedtherein.

(1) According to an aspect of this invention, there is provided avehicle control device including: a recognition unit that recognizes asurrounding situation of a vehicle; and a driving control unit thatcontrols one or both of steering and acceleration or deceleration of thevehicle on the basis of the surrounding situation recognized by therecognition unit, wherein, in a case where the vehicle merges into asecond lane from a first lane in which the vehicle travels, and asection of the second lane before merging recognized by the recognitionunit is downhill, the driving control unit makes a speed or accelerationof the vehicle during merging higher than in a case where the sectionbefore merging is not downhill.

(2) In the aspect of the above (1), in a case where the vehicle mergesinto the second lane from the first lane, and the section of the secondlane before merging is downhill, the driving control unit makes a targetspeed or target acceleration of the vehicle during merging higher thanin a case where the section before merging is not downhill.

(3) In the above (1), in a case where the vehicle merges into the secondlane from the first lane, and the section of the second lane beforemerging is downhill, the driving control unit accelerates the vehiclebefore merging to make a speed during entrance into the second lanehigher than in a case where the section before merging is not downhill.

(4) In the aspect of the above (1), in a case where the vehicle mergesinto the second lane from the first lane, and the section of the secondlane before merging is downhill, the driving control unit makes anacceleration after entrance into the second lane higher than in a casewhere the section of the second lane before merging is not downhill.

(5) In the aspect of the above (1), a sensor unit that detects a roadsituation around the vehicle is further included, and the drivingcontrol unit adjusts the speed or acceleration of the vehicle duringmerging on the basis of a detection distance of the section of thesecond lane before merging detected by the sensor unit.

(6) In the aspect of the above (1), a sensor unit that detects a roadsituation around the vehicle is further included, and in a case wherethe vehicle merges into the second lane from the first lane, and thesection of the second lane before merging is downhill, the drivingcontrol unit turns a detection direction of the sensor unit upward morethan in a case where the section before merging is not downhill.

(7) In the aspect of the above (1), the driving control unit adjusts amagnitude of the speed or acceleration of the vehicle during merging onthe basis of at least one of a gradient degree of the downhill section,a height of a top of the downhill section, or a distance of the downhillsection.

(8) According to an aspect of this invention, there is provided avehicle control method including causing a computer, comprising:recognizing a surrounding situation of a vehicle; and controlling one orboth of steering and acceleration or deceleration of the vehicle on thebasis of the recognized surrounding situation, wherein, in a case wherethe vehicle merges into a second lane from a first lane in which thevehicle travels, and a section of the second lane before merging isdownhill, a speed or acceleration of the vehicle is made higher than ina case where the section before merging is not downhill.

(9) According to an aspect of this invention, there is provided astorage medium having a program stored therein, the program causing acomputer to: recognize a surrounding situation of a vehicle; and controlone or both of steering and acceleration or deceleration of the vehicleon the basis of the recognized surrounding situation, wherein, in a casewhere the vehicle merges into a second lane from a first lane in whichthe vehicle travels, and a section of the second lane before merging isdownhill, a speed or acceleration of the vehicle is made higher than ina case where the section before merging is not downhill.

According to (1) to (9), it is possible to execute more appropriatedriving control on the basis of a road situation during merging.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a configuration diagram of a vehicle system in which a vehiclecontrol device according to an embodiment is used.

FIG. 2 is a functional configuration diagram of a first control unit anda second control unit.

FIG. 3 is a diagram showing processes which are performed by a mergingcontrol unit.

FIG. 4 is a diagram of a plurality of lanes viewed from a lateraldirection (Y-axis direction).

FIG. 5 is a diagram showing a change in the speed of a host vehicleduring merging into a lane.

FIG. 6 is a diagram showing processes which are performed by the mergingcontrol unit in a case where a stop line is present in the vicinity of amerging point.

FIG. 7 is a diagram showing a change in the speed of the host vehicle ina case where the stop line is present in the vicinity of the mergingpoint.

FIG. 8 is a diagram showing a detection distance based on a sensor unit.

FIG. 9 is a diagram showing a detection distance in a case where thedetection direction of the sensor unit is turned upward.

FIG. 10 is a flow chart showing a flow of processes which are executedby a driving control device of the embodiment.

FIG. 11 is a diagram showing an example of a hardware configuration ofthe driving control device of the embodiment.

DESCRIPTION OF EMBODIMENTS

Hereinafter, an embodiment of a vehicle control device, a vehiclecontrol method, and a storage medium of the present invention will bedescribed with reference to the accompanying drawings. The vehiclecontrol device of the embodiment is applied to an autonomous drivingvehicle. The term “autonomous driving” refers to, for example,controlling one or both of the steering and acceleration or decelerationof a vehicle and executing driving control. The above-described drivingcontrol also includes, for example, control for assisting an occupant'sdriving operation such as an adaptive cruise control system (ACC) or alane keeping assistance system (LKAS). In the following, a case whererules of left-hand traffic are applied will be described, but in a casewhere rules of right-hand traffic are applied, the right and left may beinterchanged.

[Overall Configuration]

FIG. 1 is a configuration diagram of a vehicle system 1 in which avehicle control device according to an embodiment is used. A vehiclehaving the vehicle system 1 mounted therein (hereinafter referred to asa host vehicle M) is, for example, a two-wheeled, three-wheeled, orfour-wheeled vehicle or the like, and the driving source thereof is aninternal-combustion engine such as a diesel engine or a gasoline engine,an electric motor, or a combination thereof. The electric motor operatesusing power generated by a generator connected to an internal-combustionengine or discharging power of a secondary battery or a fuel cell.

The vehicle system 1 includes, for example, a camera 10, a radar device12, a viewfinder 14, an object recognition device 16, a communicationdevice 20, a human machine interface (HMI) 30, a vehicle sensor 40, anavigation device 50, a map positioning unit (MPU) 60, a drivingoperator 80, a driving control device 100, a traveling drive forceoutput device 200, a brake device 210, and a steering device 220. Thesedevices or instruments are connected to each other through a multiplexcommunication line such as a controller area network (CAN) communicationline, a serial communication line, a wireless communication network, orthe like. The configuration shown in FIG. 1 is merely an example, andportions of the configuration may be omitted, or other configurationsmay be further added thereto. A combination of the camera 10, the radardevice 12, and the viewfinder 14 is an example of a “sensor unit.”

The camera 10 is a digital camera using a solid-state imaging elementsuch as, for example, a charge coupled device (CCD) or a complementarymetal oxide semiconductor (CMOS). The camera 10 is installed at anypoint on the host vehicle M. For example, in a case where a forwardimage of the host vehicle M is captured, the camera 10 is installed onthe upper portion of the front windshield, the rear surface of therear-view mirror, or the like. In a case where a rearward image of thehost vehicle M is captured, the camera 10 is installed on the upperportion of the rear windshield or the like. In a case where a rightwardor leftward image of the host vehicle M is captured, the camera 10 isinstalled on the right side, left side or the like of the car body orthe side mirror. The camera 10 may be provided with a drive unit 10Athat can change an image capture direction. The drive unit 10A moves theimage capture direction to one or both of the top and bottom or thelight and left within a predetermined range with respect to a referencedirection. The camera 10, for example, repeatedly captures an image ofthe vicinity of the host vehicle M periodically. The camera 10 may be astereo camera.

The radar device 12 radiates radio waves such as millimeter waves to thevicinity of the host vehicle M, and detects radio waves (reflectedwaves) reflected from an object included in a radiation range to detectat least the position (distance to and orientation of) of the object.The radar device 12 is installed at any point on the host vehicle M. Theradar device 12 is installed at, for example, each position of thefront, the rear, the right, and the left on the basis of each detectiondirection so that the positions of all objects in the vicinity of thehost vehicle M can be ascertained. The radar device 12 may be providedwith a drive unit 12A that can change the radiation direction of radiowaves. The drive unit 12A moves the radiation direction of radio wavesto one or both of the top and bottom or the light and left within apredetermined range with respect to a reference direction. The radardevice 12 may detect the position and speed of an object with afrequency modulated continuous wave (FMCW) system.

The viewfinder 14 is a light detection and ranging (LIDAR) viewfinder.The viewfinder 14 irradiates the vicinity of the host vehicle M withlight, and measures scattered light. The viewfinder 14 detects adistance to an object on the basis of a time from light emission tolight reception. The irradiation light is, for example, pulsed laserlight. The viewfinder 14 is installed at any point on the host vehicleM. For example, in a case where light is radiated to the front of thehost vehicle M, the viewfinder 14 is installed on the front grill of thehost vehicle M, in the inside of the headlight, or the like. In a casewhere light is radiated to the rear of the host vehicle M, theviewfinder 14 is installed in the inside of the tail light or the like.In a case where light is radiated to the right or left of the hostvehicle M, the viewfinder 14 is installed on the right side or left sideof the car body, the side mirror, or the vicinity of a side light. Theviewfinder 14 may be provided a drive unit 14A that can change theradiation direction of light. The drive unit 14A moves the radiationdirection of light to one or both of the top and bottom or the light andleft within a predetermined range with respect to a reference direction.

The object recognition device 16 recognizes the position, type, speed,or the like of an object by performing a sensor fusion process ondetection results based on some or all of the camera 10, the radardevice 12, and the viewfinder 14. The object recognition device 16outputs recognition result to the driving control device 100. The objectrecognition device 16 may output the detection results of the camera 10,the radar device 12, and the finder 14, as they are, to the drivingcontrol device 100. The object recognition device 16 may be omitted fromthe vehicle system 1. The camera 10 includes an infrared camera thatimages a change in the surface temperature of an object in addition to acamera that capture of a normal image. The camera 10 may switch betweennormal imaging and infrared imaging through the function of the camera.

The communication device 20 communicates another vehicle which ispresent in the vicinity of the host vehicle M using, for example, acellular network, a Wi-Fi network, Bluetooth (registered trademark),dedicated short range communication (DSRC), or the like, or communicateswith server devices of various types through a wireless base station.

The HMI 30 provides various types of information for an occupant of thehost vehicle M, and accepts the occupant's input operation. The HMI 30includes various types of display devices, a speaker, a buzzer, a touchpanel, a switch, a key, a light-emitting device provided inside avehicle, and the like. A portion of the configuration of the HMI 30 maybe provided in the driving operator 80 (for example, a steering wheel).

The vehicle sensor 40 includes a vehicle speed sensor that detects thespeed of the host vehicle M, an acceleration sensor that detects anacceleration, a yaw rate sensor that detects an angular velocity arounda vertical axis, an orientation sensor that detects the direction of thehost vehicle M, or the like. The acceleration includes, for example, atleast one of longitudinal acceleration in the traveling direction of thehost vehicle M or lateral acceleration in the lateral direction of thehost vehicle M.

The navigation device 50 includes, for example, a global navigationsatellite system (GNSS) receiver 51, a navigation HMI 52, and a routedecision unit 53. The navigation device 50 holds first map information54 in a storage device such as a hard disk drive (HDD) or a flashmemory. The GNSS receiver 51 specifies the position of the host vehicleM on the basis of a signal received from a GNSS satellite. The positionof the host vehicle M may be specified or complemented by an inertialnavigation system (INS) in which an output of the vehicle sensor 40 isused. The GNSS receiver 51 may be included in the vehicle sensor 40.

The navigation HMI 52 includes a display device, a speaker, a touchpanel, a key, and the like. A portion or the entirety of the navigationHMI 52 may be shared with the above-described HMI 30. The route decisionunit 53 decides, for example, a route (hereinafter, a route on a map)from the position (or any input position) of the host vehicle Mspecified by the GNSS receiver 51 to a destination input by an occupantusing the navigation HMI 52 with reference to the first map information54. The first map information 54 is, for example, information in which aroad shape is represented by a link indicating a road and nodesconnected by the link. The first map information 54 may include thecurvature of a road, point of interest (POI) information, or the like.The first map information 54 may include information relating to aground feature. The information relating to a ground feature includes,for example, a ground feature ID which is identification information ofa ground feature, position information of a ground feature, theattribute (genre) of a ground feature, or guidance information based ona ground feature. The ground feature includes, for example, a landmark,a sightseeing area (for example, a mountain, a waterfall, or a lake),famous architecture (for example, a temple or a bridge), or commercialfacilities such as a theme park or a shopping mall. In terms of computerprocessing, the ground feature may be one point on a map, or may be aregion having a width. The information relating to a ground feature maybe set in the first map information 54 as default, or may be acquiredfrom a map server or the like through the Internet or the like. Theroute on a map is output to the MPU 60. The navigation device 50 mayperform route guidance using the navigation HMI 52 on the basis of theroute on a map. The navigation device 50 may be realized by the functionof a terminal device such as, for example, a smartphone or a tabletterminal possessed by an occupant. The navigation device 50 may transmitits current position and destination to a navigation server through thecommunication device 20, and acquire the same route as the route on amap from the navigation server.

The MPU 60 includes, for example, a recommended lane decision unit 61,and holds second map information 62 in a storage device such as an HDDor a flash memory. The recommended lane decision unit 61 divides theroute on a map provided from the navigation device 50 into a pluralityof blocks (for example, divides the route on a map every 100 [m] in avehicle traveling direction), and decides a recommended lane for eachblock with reference to the second map information 62. The recommendedlane decision unit 61 makes a decision on which lane from the left totravel along. In a case where a branch point is present in the route ona map, the recommended lane decision unit 61 decides a recommended laneso that the host vehicle M can travel along a rational route foradvancing to a branch destination.

The second map information 62 is map information having a higheraccuracy than that of the first map information 54. The second mapinformation 62 includes, for example, information of the center of alane, information of the boundary of a lane, or the like. The second mapinformation 62 includes information of the number of traveling lanes orthe positions thereof based on a road shape, the position of a passinglane, merging, divergence, or the like. The second map information 62may include identification information for identifying a downhill roador an uphill road in the traveling direction of a road, informationrelating to the gradient of a road (the inclination of a road to ahorizontal plane), the distance of a downhill road or an uphill road, orinformation of the height of the top or the like. The second mapinformation 62 may include a traffic sign, road information, trafficregulations information, address information (address or zip code),facility information, telephone number information, or the like. Thesecond map information 62 may be updated at any time by thecommunication device 20 communicating with another device.

The driving operator 80 includes, for example, an accelerator pedal, abrake pedal, a shift lever, a steering wheel, a variant steering wheel,a joystick, and other operators. A sensor that detects the amount ofoperation or the presence or absence of operation is installed on thedriving operator 80, and the detection results are output to the drivingcontrol device 100, or some or all of the traveling driving force outputdevice 200, the brake device 210, and the steering device 220.

The driving control device 100 includes, for example, a first controlunit 120, a second control unit 160, an HMI control unit 180, and astorage unit 190. Each of the components except the storage unit 190 isrealized by a hardware processor such as, for example, a centralprocessing unit (CPU) executing a program (software). Some or all ofthese components may be realized by hardware (circuit unit; includingcircuitry) such as a large scale integration (LSI), an applicationspecific integrated circuit (ASIC), a field-programmable gate array(FPGA), or a graphics processing unit (GPU), and may be realized bycooperation between software and hardware. The program may be stored inthe storage unit 190 of the driving control device 100 in advance, maybe stored in a detachable storage medium such as a DVD or a CD-ROM (anon-transitory storage medium), and may be installed in the storage unit190 of the driving control device 100 by the storage medium beingmounted in a drive device.

FIG. 2 is a functional configuration diagram of the first control unit120 and the second control unit 160. The first control unit 120includes, for example, a recognition unit 130 and a behavior plangeneration unit 140. A combination of the behavior plan generation unit140 and the second control unit 160 is an example of a “driving controlunit.”

The first control unit 120 concurrently realizes, for example, afunction based on artificial intelligence (AI) and a function based on amodel imparted in advance. For example, a function of “recognizing apoint of intersection” may be realized by the recognition of a point ofintersection based on deep learning or the like and recognition based onconditions (such as a signal for which pattern matching is possible or aroad sign) imparted in advance being concurrently executed, and beingcomprehensively evaluated by performing scoring on both. Thereby, thereliability of autonomous driving is secured.

The recognition unit 130 recognizes the surrounding situation of thehost vehicle M on the basis of, for example, information which is inputfrom the camera 10, the radar device 12, and the viewfinder 14 throughthe object recognition device 16. For example, the recognition unitrecognizes the state of the position, direction, speed, acceleration,and the like of an object which is present in the vicinity of the hostvehicle M. Examples of the object include a moving object such as apedestrian or another vehicle, an obstacle such as a construction point,or a building such as a bridge. The position of the object is recognizedas, for example, a position in relative coordinates with arepresentative point (such as the centroid or the center of a driveshaft) of the host vehicle M as an origin, and is used in control. Theposition of the object may be represented by a representative point suchas the centroid or a corner of the object, or may be represented by arepresentative region. The “state” of the object may include theacceleration or jerk of the object, or “behavior state” (for example,whether it is performing or attempting to perform a lane change).

The recognition unit 130 recognizes, for example, a lane (travelinglane) in which the host vehicle M is traveling as the surroundingsituation of the host vehicle M. For example, the recognition unit 130may recognize a traveling lane by comparing a pattern of a roadpartition line (for example, an array of solid lines and broken lines)obtained from the second map information 62 with a pattern of a roadpartition line located in the vicinity of the host vehicle M which isrecognized from an image captured by the camera 10. The recognition unit130 may recognize a traveling lane by recognizing a driving boundary(road boundary) including a road partition line, a shoulder, acurbstone, a median strip, a guardrail, or the like without beinglimited to the recognition of a road partition line. In thisrecognition, the position of the host vehicle M acquired from thenavigation device 50 or processing results based on an INS may be added.The recognition unit 130 may recognize the width, height, shape, or thelike of an obstacle or a building on the basis of an image captured bythe camera 10, or recognize characters, signs or the like drawn on theroad surface of a road. The recognition unit 130 may recognize, forexample, a merging point, a divergence point, the road shape of a laneafter merging (for example, whether it is a sloping road (uphill ordownhill)), or the like on the basis of one or both of the second mapinformation 62 or an image captured by the camera 10. The recognitionunit 130 may recognize a sidewalk, a stop line (including a temporarystop line), an obstacle, a red light, a tollbooth, a road structure, andother road events.

Upon recognizing a traveling lane, the recognition unit 130 recognizesthe position or posture of the host vehicle M with respect to thetraveling lane. The recognition unit 130 may recognize, for example,deviation of the host vehicle M from the center of the lane which is areference point, and an angle formed with respect to a line aligned withthe center of the lane of the host vehicle M in its traveling directionas the relative position and posture of the host vehicle M with respectto the traveling lane. Instead, the recognition unit 130 may recognizethe position of the reference point of the host vehicle M or the likewith respect to either lateral end portion (a road partition line or aroad boundary) of the traveling lane as the relative position of thehost vehicle M with respect to the traveling lane. The recognition unit130 may recognize structures on a road (such as, for example, atelephone pole or a median strip) on the basis of the first mapinformation 54 or the second map information 62.

The behavior plan generation unit 140 generates a target trajectoryalong which the host vehicle M will travel in the future automatically(irrespective of a driver's operation) so that the host vehicle Mtravels along the recommended lane decided by the recommended lanedecision unit 61 in principle and can cope with the peripheral situationof the host vehicle. The target trajectory includes, for example, aspeed element. For example, the target trajectory may be represented asa trajectory obtained by arranging points (trajectory points) at whichthe host vehicle M will arrive in order. The trajectory points arepoints at which the host vehicle M will arrive after predeterminedtraveling distances (for example, approximately every several [m]) whichis a distance along a road. Separately from the trajectory points, atarget speed and a target acceleration for each predetermined samplingtime (for example, approximately several tenths of a [sec]) aregenerated as a portion of the target trajectory. The trajectory pointsmay be positions at which the host vehicle M will arrive at samplingtimes for respective predetermined sampling times. In this case,information of target speed or target acceleration is represented by aninterval between trajectory points.

The behavior plan generation unit 140 may set autonomous driving eventswhen generating a target trajectory. Examples of autonomous drivingevents include a constant-speed traveling event, a low-speed followingtraveling event, a lane change event, a diverging event, a mergingevent, a contact avoidance event, and the like. The merging event is,for example, an event of causing the host vehicle M to merge into a mainline at a merging point. The behavior plan generation unit 140 generatesa target trajectory according to a started event. The function of amerging control unit 142 of the behavior plan generation unit 140 willbe described later.

The second control unit 160 controls the traveling driving force outputdevice 200, the brake device 210, and the steering device 220 so thatthe host vehicle M passes along the target trajectory generated by thebehavior plan generation unit 140 according to scheduled times.

The second control unit 160 includes, for example, an acquisition unit162, a speed control unit 164, and a steering control unit 166. Theacquisition unit 162 acquires information of the target trajectory(trajectory point) generated by the behavior plan generation unit 140,and stores the acquired information in a memory (not shown). The speedcontrol unit 164 controls the traveling driving force output device 200or the brake device 210 on the basis of a speed element associated withthe target trajectory stored in the memory. The steering control unit166 controls the steering device 220 in accordance with the bent stateof the target trajectory stored in the memory. The processes of thespeed control unit 164 and the steering control unit 166 are realizedby, for example, a combination of feedforward control and feedbackcontrol. As an example, the steering control unit 166 executes acombination of feedforward control according to the curvature of a roadin front of the host vehicle M and feedback control based on deviationfrom the target trajectory.

Referring back to FIG. 1 , the HMI control unit 180 causes the HMI 30 tonotify an occupant of predetermined information. The predeterminedinformation is, for example, information relevant to traveling of thehost vehicle M such as information relating to the state of the hostvehicle M or information relating to driving control. The predeterminedinformation may include information that is not relevant to traveling ofthe host vehicle M, such as a television program, or content stored in astorage medium such as a DVD (for example, a movie). The HMI controlunit 180 may output information accepted by the HMI 30 to thecommunication device 20, the navigation device 50, the first controlunit 120, or the like.

The storage unit 190 is realized by, for example, a non-volatile storagedevice such as a read only memory (ROM), an electrically erasable andprogrammable read only memory (EEPROM), or an HDD, and a volatilestorage device such as a random access memory (RAM) or a register. Forexample, information for realizing driving control of the host vehicle Mor other information of various types is stored in the storage unit 190.

The traveling driving force output device 200 outputs a travelingdriving force (torque) for a vehicle to travel to a driving wheel. Thetraveling driving force output device 200 includes, for example, acombination of an internal-combustion engine, an electric motor, atransmission or the like, and an electronic control unit (ECU) thatcontrols these components. The ECU controls the above components inaccordance with information which is input from the second control unit160 or information which is input from the driving operator 80.

The brake device 210 includes, for example, a brake caliper, a cylinderthat transfers hydraulic pressure to the brake caliper, an electricmotor that generates hydraulic pressure in the cylinder, and a brakeECU. The brake ECU controls the electric motor in accordance with theinformation which is input from the second control unit 160 or theinformation which is input from the driving operator 80, and causes abrake torque according to a braking operation to be output to eachwheel. The brake device 210 may include a mechanism that transfershydraulic pressure generated by the operation of a brake pedal includedin the driving operator 80 through a master cylinder to the cylinder asa backup. The brake device 210 is not limited to the above-describedconfiguration, and may be an electronic control type hydraulic brakedevice that controls an actuator in accordance with the informationwhich is input from the second control unit 160 and transfers hydraulicpressure of the master cylinder to the cylinder.

The steering device 220 includes, for example, a steering ECU and anelectric motor. The electric motor changes the direction of a turningwheel, for example, by causing a force to act on a rack and pinionmechanism. The steering ECU drives the electric motor in accordance withthe information which is input from the second control unit 160 or theinformation which is input from the driving operator 80, and changes thedirection of the turning wheel.

[Function of Merging Control Unit]

Next, the details of the function of the merging control unit 142 willbe described. The function of the merging control unit 142 shown belowmay be a function which is executed in a merging event, or may be afunction in other merging control.

For example, in a case where the host vehicle M merges into a main line(an example of a second lane) from a merging lane (an example of a firstlane) in which the host vehicle is traveling, the merging control unit142 generates a target trajectory on the basis of a predeterminedcondition. FIG. 3 is a diagram showing processes which are performed bythe merging control unit 142. The example of FIG. 3 shows a main line(lanes L1 and L2) extending in an X-axis direction and a merging lane(lane L3) that merges from the left side in the traveling direction ofthe lane L1. In the example of FIG. 3 , the host vehicle M is assumed toexecute autonomous driving along a route to a destination which is setby the navigation device 50, and to be traveling in the lane L3 toward amerging point P1. The merging point P1 is a point at which the lane L1and the lane L3 are connected to each other. The merging point P1 may bedefined as the position of a line extending from the connection point inthe direction of a vehicle width (a Y-axis direction in the drawing)when viewed from the lanes L1 and L2, or may be defined as the positionof a line obtained by linking respective points at which right and leftroad partition lines partitioning the lane L3 are connected to the laneL1 when viewed from the lane L3. In the example of FIG. 3 , it isassumed that a stop line is not present in the vicinity of the mergingpoint P1 (at a position within a predetermined range from the mergingpoint P1). In the example of FIG. 3 , points P2, P3, and Pa to Pc may bepositions of lines extending in the direction of a vehicle width. In theexample of FIG. 3 , another vehicle m1 is assumed to be traveling in thelane L1.

FIG. 4 is a diagram of the lanes L1 and L2 viewed from a lateraldirection (a Y-axis direction in the drawing). In the example of FIG. 4, for convenience, the lane L3 and the host vehicle M conforming to thedirection of the same three-dimensional (XYZ) axis as FIG. 3 are shownso that the positions of the lane L3 and the host vehicle M with respectto the lanes L1 and L2 can be ascertained. The lanes L1 and L2 form adownhill road in a section from the point P2 to the point P3 as shown inFIG. 4 .

In this situation, first, the merging control unit 142 determineswhether the host vehicle merges into the lane L1 from the lane L3 on thebasis of a route to a destination. In a case where it is determined thatthe host vehicle merges into the lane L1, the merging control unit 142determines whether a predetermined section of the lane L1 before mergingis downhill. The predetermined section before merging is, for example, aroad section in front of the merging point P1, and is a section in whicha distance from the merging point P1 is equal to or less than athreshold. For example, the merging control unit 142 refers to thesecond map information 62 on the basis of information relating to thecurrent position and the traveling direction of the host vehicle M, andacquires information relating to the gradient of the predeterminedsection of the lane L1 before merging. In a case where an inclinationangle θ1 of a road surface included in the information relating to agradient is larger than a threshold angle θth, the merging control unit142 determines that the predetermined section of the lane L1 beforemerging is downhill. The merging control unit 142 may determine whetherthe predetermined section of the lane L1 before merging is downhill onthe basis of identification information for identifying whether the roadis downhill or uphill included in the second map information 62. Themerging control unit 142 may perform an analysis based on patternmatching or the like on the basis of an image captured by the camera 10,and determine whether the predetermined section of the lane L1 beforemerging is downhill on the basis of an analysis result. In a case whereit is recognized that there is a bridge in front of the merging point P1on the basis of the second map information 62, the merging control unit142 may determine that the road is downhill due to the bridge.

Next, in a case where it is determined that the predetermined section ofthe lane L1 before merging is downhill, the merging control unit 142makes the speed or acceleration of the host vehicle M higher than in acase where the predetermined section before merging is not downhill. Aroad which is not downhill includes a road having a low gradient degreein which the inclination angle θ1 is equal to or less than thepredetermined angle θth, or an uphill road. For example, in a case wherethe section of the lane L1 before merging is downhill, the mergingcontrol unit 142 sets a target speed higher than a target speed in acase where the section before merging is not downhill, and generates atarget trajectory on the basis of the set target speed. The speedcontrol unit 164 controls the speed or acceleration of the host vehicleM so as to approximate the target speed on the basis of the generatedtarget trajectory. As a result, the speed or acceleration of the hostvehicle M during merging becomes higher. Instead of the target speed,the merging control unit 142 may set a target acceleration higher than atarget acceleration in a case where the section before merging is notdownhill. In the following, an example in which a target speed is sethigher will be mainly described.

FIG. 5 is a diagram showing a change in the speed of the host vehicle Mduring merging into the lane L1. In FIG. 5 , the horizontal axisrepresents a point P at which the host vehicle M travels, and thevertical axis represents a target speed Vt of the host vehicle M. It isassumed that, on the horizontal axis, the left side of the merging pointP1 represents points in the lane L3, and the right side of the mergingpoint P1 represents points in the lane L1. In the example of FIG. 5 ,the host vehicle M is assumed to be traveling at a speed V0 in the laneL3 before merging.

In a case where the predetermined section of the lane L1 before mergingis not downhill, the merging control unit 142 sets a target speed ateach point so that the target speed Vt is set to a speed V1 at the pointPc of the lane L1 after merging. As a result, the speed control unit 164executes feedback control of the speed of the host vehicle M so as toattain the speed V1 at the point Pc according to the set target speed.

In a case where the section of the lane L1 before merging is downhill,the merging control unit 142 sets a target speed at each point so thatthe target speed Vt at the point Pc is set to a speed V2 higher than thespeed V1 in a case where it is not downhill. The magnitude of the targetspeed may be adjusted on the basis of at least one of, for example, thegradient degree of the downhill road of the lane L1, the height of thetop of the downhill road of the lane L1, or the distance of the downhillroad. Thereby, it is possible to execute more appropriate mergingcontrol on the basis of the road situation. The upper limit of themagnitude of the target speed is set on the basis of, for example, thespeed limit of the lane L1, the road shape of a merging point, or thelike. Thereby, the host vehicle M can merge into the lane L1 withsmoother behavior.

In a case where the predetermined section of the lane L1 before mergingis downhill, the merging control unit 142 may make a timing at whichacceleration control is started earlier than a timing in a case wherethe predetermined section before merging is not downhill. In the exampleof FIG. 5 , in a case where the predetermined section of the lane L1before merging is downhill, a speed during entrance into the lane L1 ismade higher by starting an acceleration at the point Pb in front of theacceleration start position Pa in a case where it is not downhill withrespect to the merging point P1. The speed during entrance is, forexample, a speed at a point in time when at least a portion of the hostvehicle M is present on the lane L1. Thereby, the merging control unit142 suppresses a sudden acceleration of the host vehicle M duringmerging, thereby allowing smooth speed control to be executed.

By performing merging control based on the above-described speedcontrol, it is possible to reduce a risk of the host vehicle M andanother vehicle m1 coming into contact with each other even in a casewhere another vehicle m1 traveling on a downhill road gains accelerationdue to the downhill road. Even in a situation in which another vehiclewhich is present above a downhill road or on an uphill road behind thedownhill road is not able to be detected by the sensor unit, it ispossible to reduce a risk of coming into contact with another vehicle bymaking a speed during merging higher than in the case of not beingdownhill. In a case where an object such as another vehicle m1 isrecognized in the vicinity of the host vehicle M by the recognition unit130, the merging control unit 142 generates a target trajectory foravoiding contact with an object in addition to the above-described speedcontrol, and executes driving control along the generate targettrajectory.

Next, processes of the merging control unit 142 in a case where a stopline is present in the vicinity of the merging point P1 will bedescribed. FIG. 6 is a diagram showing processes of the merging controlunit 142 in a case where a stop line SL is present in the vicinity ofthe merging point P1. In the example of FIG. 6 , the stop line SL isassumed to be drawn at a point Ps in front of the merging point P1 inthe lane L3.

In this case, first, the merging control unit 142 determines whether astop line is present in the vicinity of the merging point P1 on thebasis of a recognition result of the recognition unit 130. The stop linemay be a stop line drawn on a road or a character of “STOP.”. It may bedetermined whether a road sign for stopping a vehicle is recognizedinstead of the stop line. In a case where the stop line is not present,the merging control unit 142 executes speed control as shown in FIGS. 3to 5 described above. In a case where the stop line SL is present, themerging control unit 142 generates a target trajectory for stopping thehost vehicle M in front (for example, several centimeters to severaltens of centimeters ahead) of the point Ps at which the stop line SL ispresent. In a case where the host vehicle M is caused to merge into thelane L1 from a stop position, and the predetermined section of the laneL1 before merging is downhill, the merging control unit 142 makes thespeed or acceleration of the host vehicle M after entrance into the laneL1 higher than in a case where it is not downhill. The wording “afterentrance” refers to, for example, a time after entrance.

FIG. 7 is a diagram showing a change in the speed of the host vehicle Min a case where the stop line SL is present in the vicinity of themerging point P1. In FIG. 7 , the horizontal axis represents a point Pat which the host vehicle M travels, and the vertical axis represents atarget speed Vt of the host vehicle M. It is assumed that, on thehorizontal axis, the left side of the merging point P1 represents pointsin the lane L3, and the right side of the merging point P1 representspoints in the lane L1. The example of FIG. 7 shows a state of a changein the speed of the host vehicle M after temporary stop (speed V=0) atthe point Ps.

The merging control unit 142 temporarily stops the host vehicle M infront of the point Ps on the stop line SL, and then generates a targettrajectory in which the host vehicle passes through the merging point P1at a predetermined speed and enters the lane L1. In a case where thehost vehicle M enters the lane L1, and then the predetermined section ofthe lane L1 before merging is not downhill, the merging control unit 142sets a target speed so that the target speed Vt of the host vehicle M isset to a speed V1 # at the point Pc, and generates a target trajectoryon the basis of the set target speed.

In a case where the host vehicle M enters the lane L1, and then thepredetermined section of the lane L1 before merging is downhill, themerging control unit 142 sets a target speed so that the target speed Vtof the host vehicle M is set to a speed V2 # higher than the speed V1 #at the point Pc, and generates a target trajectory on the basis of theset target speed. Thereby, in a case where the stop line SL is presentat the merging point P1, as shown in FIG. 7 , it is possible to executemore appropriate driving control by increasing an acceleration afterentrance into the lane L1.

The merging control unit 142 may control the magnitude of a speed atwhich the host vehicle M enters the lane L1 on the basis of a detectiondistance of a road shape of a predetermined section of the lane L1before merging which is detected by the camera 10, the radar device 12,or the viewfinder 14 during merging. FIG. 8 is a diagram showing adetection distance based on the sensor unit. The example of FIG. 8 showsa detection range A1 in the rear of the host vehicle M after the hostvehicle M merges into the lane L1 (a predetermined section of the laneL1 before merging). This detection range A1 is, for example, a rangewhich is detected by the camera 10 installed on the upper portion of therear windshield, the radar device 12 installed in the rear of the carbody, or the viewfinder 14 installed inside a tail light. The detectionrange A1 differs depending on a distance from the merging point P1, thegradient degree (inclination angle θ1) of a downhill road, or the like

The merging control unit 142 acquires a detection distance D1 at which adistance from the host vehicle M becomes maximum in the detection rangeA1 in the rear of the host vehicle M which can be detected by the sensorunit. The merging control unit 142 then sets a target speed on the basisof the detection distance D1. For example, as the detection distance D1becomes shorter, the gradient degree of a downhill road becomes higher(sudden gradient), and thus the speed of the following vehicle (forexample, another vehicle m1) is estimated to have a tendency to becomehigher. As the detection distance D1 becomes shorter, there is thepossibility of the recognition unit 130 not being able to recognize thefollowing vehicle which is present closer to the host vehicle M.Therefore, as the detection distance D1 becomes shorter, the mergingcontrol unit 142 performs an adjustment so that the speed oracceleration of the host vehicle M after merging becomes higher.Thereby, it is possible to suppress contact with the following vehicle,and to execute smooth merging control.

In a case where the predetermined section of the lane L1 before mergingis downhill, the merging control unit 142 may turn the detectiondirection of the sensor unit upward more than in a case where thepredetermined section before merging is not downhill. FIG. 9 is adiagram showing a detection distance in a case where the detectiondirection of the sensor unit is turned upward. The example of FIG. 9shows a detection range A2 in the rear of the host vehicle M in a casewhere the host vehicle M is present at the same point as that in FIG. 8.

In a case where it is determined that the predetermined section of themerging lane L1 before merging is a sloping road, the merging controlunit 142 drives at least one drive unit of the drive units 10A, 12A, and14A of the camera 10, the radar device 12, and the viewfinder 14,respectively, installed at positions where the rear of the host vehicleM serves as a detection target, and moves the detection range of targetdevices (the camera 10, the radar device 12, and the viewfinder 14)upward. In this case, the merging control unit 142 may turn thedetection range upward by a fixed angle in a reference direction, or mayset an angle turned upward on the basis of at least one of the gradientdegree of a downhill road, the height of the top of the downhill road,and the distance of the downhill road. Thereby, as shown in FIG. 9 , itis possible to detect an object in the detection range A2 including aportion located further upward than the detection range A1 shown in FIG.8 , and to early detect another vehicle m1 which is present above adownhill road. Therefore, the host vehicle M can perform appropriatedriving control based on a detection result.

The merging control unit 142 may recognize a direction in which adownhill road is present at a point by a predetermined distance aheadfrom the merging point P1 at a point in time when the host vehicle M istraveling in the lane L3 instead of (or in addition to) theabove-described direction control of the sensor unit, and turn upward atleast one of the camera 10, the radar device 12, and the viewfinder 14in a detection range included in the recognized direction. For example,in a case where the host vehicle M is present at the point Ps shown inFIG. 6 , the merging control unit 142 turns upward the at least one ofthe camera 10, the radar device 12, and the viewfinder 14 in which theright side of the host vehicle M is included in a detection range.

As described above, instead of turning a target device upward, themerging control unit 142 may expand the detection range of the targetdevice upward through switching between modes of the target device orthe like. After merging is ended and then a predetermined time haselapsed, the merging control unit 142 moves the detection direction ofthe sensor unit turned upward to an original direction (for example, areference direction).

[Process Flow]

FIG. 10 is a flow chart showing a flow of processes which are executedby the driving control device 100 of the embodiment. The processes ofthe present flow chart will be described mainly with a focus on a speedcontrol process based on autonomous driving during merging. Theprocesses of the present flow chart may be repeatedly executed, forexample, in a predetermined period or at a predetermined timing. In theexample of FIG. 10 , driving control is assumed to be executed on thebasis of a route to a destination.

First, the recognition unit 130 recognizes the surrounding situation ofthe host vehicle M (step S100). Next, the merging control unit 142determines whether the host vehicle merges into another lane from atraveling lane on the basis of the surrounding situation recognized bythe recognition unit 130 (step S102). In a case where it is determinedthat the host vehicle merges into another lane, the merging control unit142 determines whether a predetermined section of a lane after mergingbefore merging is downhill (step S104). In a case where it is determinedthat the predetermined section of the other lane is downhill beforemerging, the merging control unit 142 determines whether a stop line ispresent at a merging point (step S106).

In a case where it is determined that the stop line is not present atthe merging point, the merging control unit 142 sets a target speed ofthe host vehicle M higher than a target speed in the case of not beingdownhill (step S108). Next, the merging control unit 142 increases thespeed or acceleration of the host vehicle M on the basis of the settarget speed (step S110), and executes driving control for performingmerging into another lane (step S112).

In the process of step S106, in a case where it is determined that thestop line is present at the merging point, the merging control unit 142performs merging control after the host vehicle is stopped in front ofthe stop line (step S114). Next, the merging control unit 142 sets thetarget speed of the host vehicle M after merging higher than a targetspeed in the case of not being downhill (step S116). Next, the mergingcontrol unit 142 executes driving control for increasing the speed oracceleration of the host vehicle M on the basis of the set target speed(step S118).

In the process of step S104, in a case where it is determined that thepredetermined section of the other lane is not downhill before merging,the second control unit 160 sets a target speed based on the surroundingsituation by a reference set in advance (step S120), and executesdriving control for performing merging on the basis of the set targetspeed (step S122). Thereby, the processes of the present flow chart areended. In the process of step S102, in a case where it is determinedthat the host vehicle does not merge into another lane, the processes ofthe present flow chart are ended.

According to the above-described embodiment, the driving control device100 can execute more appropriate driving control on the basis of theroad situation during merging. Specifically, in the embodiment, in acase where the predetermined section of the main line before merging isdownhill during merging into the main line from the merging lane, thedriving control device 100 makes a speed or acceleration during merginghigher than in the case of not being downhill on the basis of the roadsituation regardless of the presence or absence of a rearward vehicle.Thereby, even in a case where a rearward vehicle which is present abovea downhill road or on an uphill road behind the downhill road is notable to be detected by the sensor unit, or a case where the rearwardvehicle is accelerating due to the downhill road, it is possible toexecute merging control through an appropriate speed. According to thedriving control device 100 of the embodiment, it is possible to executemerging control through a more appropriate speed by adjusting the degreeof the magnitude of the speed or acceleration of the host vehicle M onthe basis of the presence or absence of the stop line at the mergingpoint, a detection distance based on the sensor unit, the gradientdegree of a downhill road, the height of the top of the downhill road,the distance of the downhill road, or the like.

According to the above-described embodiment, in a case where thepredetermined section of the other lane is downhill before merging, itis possible to early detect another vehicle which is present above adownhill road by turning the direction of the sensor unit upward. As aresult, it is possible to execute more appropriate merging control.

In addition to the above-described control, in a case where the sectionof the lane L1 at the merging point or after merging is downhill, themerging control unit 142 may perform speed control different from thatin a case where the section of the lane L1 at the merging point or aftermerging is not downhill. For example, in a case where the section of thelane L1 at the merging point or after merging is downhill, it isconceivable that acceleration due to traveling on a downhill roadoccurs. Therefore, in a case where the section of the lane L1 at themerging point or after merging is downhill, the merging control unit 142adjusts the amount of increase in the speed or acceleration of the hostvehicle M during merging smaller than in a case where it is not downhillon the basis of the gradient degree of the downhill road at the mergingpoint or after merging, the distance of the downhill road, or the like.

[Hardware Configuration]

FIG. 11 is a diagram showing an example of a hardware configuration ofthe driving control device 100 of the embodiment. As shown in thedrawing, the driving control device 100 is configured such that acommunication controller 100-1, a CPU 100-2, a RAM 100-3 used as aworking memory, a ROM 100-4 that stores a boot program or the like, aflash memory, a storage device 100-5 such as an HDD, a drive device100-6, and the like are connected to each other through an internal busor a dedicated communication line. The communication controller 100-1performs communication with components other than the driving controldevice 100. The storage device 100-5 stores a program 100-5 a executedby the CPU 100-2. This program is developed into the RAM 100-3 by adirect memory access (DMA) controller (not shown) or the like, and isexecuted by the CPU 100-2. Thereby, some or all of the components of thedriving control device 100 are realized.

The above-described embodiment can be represented as follows.

A vehicle control device including:

a storage device having a program stored therein; and

a hardware processor,

wherein the hardware processor executes the program stored in thestorage, to thereby

recognize a surrounding situation of a vehicle, and

control one or both of steering and acceleration or deceleration of thevehicle on the basis of the recognized surrounding situation,

wherein, in a case where the vehicle merges into a second lane from afirst lane in which the vehicle travels, and a section of the secondlane before merging is downhill, a speed or acceleration of the vehicleis made higher than in a case where the section before merging is notdownhill.

While preferred embodiments of the invention have been described andshown above, it should be understood that these are exemplary of theinvention and are not to be considered as limiting. Additions,omissions, substitutions, and other modifications can be made withoutdeparting from the spirit or scope of the present invention.Accordingly, the invention is not to be considered as being limited bythe foregoing description, and is only limited by the scope of theappended claims.

What is claimed is:
 1. A vehicle control device comprising a processor,the processor configured to: recognize a surrounding situation of avehicle; and control one or both of steering and acceleration ordeceleration of the vehicle on a basis of the surrounding situation,wherein, in response to determining, based on the surrounding situation,that the vehicle is traveling in a first lane and merges into a secondlane from the first lane, and a section of the second lane beforemerging is determined to be downhill, increasing a speed or accelerationof the vehicle during merging with respect to a case where the sectionbefore merging is not determined to be downhill, wherein the first laneultimately terminates at a defined future distance.
 2. The vehiclecontrol device according to claim 1, wherein, in a case where thevehicle merges into the second lane from the first lane, and the sectionof the second lane before merging is determined to be downhill,accelerating the vehicle before merging to make a speed during entranceinto the second lane higher with respect to a case where the sectionbefore merging is not determined to be downhill.
 3. The vehicle controldevice according to claim 1, wherein, in a case where the vehicle mergesinto the second lane from the first lane, and the section of the secondlane before merging is determined to be downhill, accelerating afterentrance into the second lane with respect to a case where the sectionof the second lane before merging is not determined to be downhill. 4.The vehicle control device according to claim 1, further comprising asensor unit that detects a road situation around the vehicle, whereinthe processor adjusts the speed or acceleration of the vehicle duringmerging on a basis of a detection distance, which is detected by thesensor unit, of the section of the second lane before merging.
 5. Thevehicle control device according to claim 1, further comprising a sensorunit that detects a road situation around the vehicle, wherein, in acase where the vehicle merges into the second lane from the first lane,and the section of the second lane before merging is downhill, theprocessor turns a detection direction of the sensor unit upward morethan in a case where the section before merging is not determined to bedownhill.
 6. The vehicle control device according to claim 1, whereinthe processor adjusts a magnitude of the speed or acceleration of thevehicle during merging on a basis of at least one of a gradient degreeof the downhill section, a height of a top of the downhill section, or adistance of the downhill section.
 7. The vehicle control deviceaccording to claim 1, wherein, in a case where the vehicle merges intothe second lane from the first lane, and the section of the second lanebefore merging is determined to be downhill, increasing a target speedor target acceleration of the vehicle during merging with respect to acase where the section before merging is not determined to be downhill.8. The vehicle control device according to claim 1, wherein, in responseto determining, based on the surrounding situation, that the vehicle istraveling in the first lane and merges into the second lane from thefirst lane, and a section of the second lane before merging is notdetermined to be downhill, increasing a speed of the vehicle beforemerging so that a target speed or target acceleration of the vehicleduring merging is set to a first speed or acceleration, and wherein, inresponse to determining, based on the surrounding situation, that thevehicle is traveling in the first lane and merges into the second lanefrom the first lane, and a section of the second lane before merging isdetermined to be downhill, increasing a speed of the vehicle beforemerging so that the target speed or target acceleration of the vehicleduring merging is set to a second speed or acceleration higher than thefirst speed or acceleration.
 9. A vehicle control method causing acomputer, comprising: recognizing a surrounding situation of a vehicle;and controlling one or both of steering and acceleration or decelerationof the vehicle on a basis of the surrounding situation, wherein, inresponse to determining, based on the surrounding situation, that thevehicle is traveling in a first lane and merges into a second lane fromthe first lane, and a section of the second lane before merging isdetermined to be downhill, increasing a speed or acceleration of thevehicle during merging with respect to a case where the section beforemerging is not determined to be downhill, wherein the first laneultimately terminates at a defined future distance.
 10. The vehiclecontrol method according to claim 9, wherein, in response todetermining, based on the surrounding situation, that the vehicle istraveling in the first lane and merges into the second lane from thefirst lane, and a section of the second lane before merging is notdetermined to be downhill, increasing a speed of the vehicle beforemerging so that a target speed or target acceleration of the vehicleduring merging is set to a first speed or acceleration, and wherein, inresponse to determining, based on the surrounding situation, that thevehicle is traveling in the first lane and merges into the second lanefrom the first lane, and a section of the second lane before merging isdetermined to be downhill, increasing a speed of the vehicle beforemerging so that the target speed or target acceleration of the vehicleduring merging is set to a second speed or acceleration higher than thefirst speed or acceleration.
 11. A non-transitory storage medium havinga program stored therein, the program causing a computer to: recognize asurrounding situation of a vehicle; and control one or both of steeringand acceleration or deceleration of the vehicle on a basis of thesurrounding situation, wherein, in response to determining, based on thesurrounding situation, that the vehicle is traveling in a first lane andmerges into a second lane from the first lane, and a section of thesecond lane before merging is determined to be downhill, increasing aspeed or acceleration of the vehicle during merging with respect to acase where the section before merging is not determined to be downhill,wherein the first lane ultimately terminates at a defined futuredistance.
 12. The non-transitory storage medium according to claim 11,wherein, in response to determining, based on the surrounding situation,that the vehicle is traveling in the first lane and merges into thesecond lane from the first lane, and a section of the second lane beforemerging is not determined to be downhill, increasing a speed of thevehicle before merging so that a target speed or target acceleration ofthe vehicle during merging is set to a first speed or acceleration, andwherein, in response to determining, based on the surrounding situation,that the vehicle is traveling in the first lane and merges into thesecond lane from the first lane, and a section of the second lane beforemerging is determined to be downhill, increasing a speed of the vehiclebefore merging so that the target speed or target acceleration of thevehicle during merging is set to a second speed or acceleration higherthan the first speed or acceleration.